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Stability of 4-DMAP in solution.

D P Wang·L C Chang·M T Wang
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Abstract

A stability-indicating reversed-phase performance liquid chromatographic method was developed for the detection of 4-(N,N-dimethylamino)phenol (4-DMAP) and its degradation products under accelerated degradation conditions. The degradation kinetics of 4-DMAP in aqueous solution over a pH range of 1.12-6.05 and its stability in solutions based on propylene glycol or polyethylene glycol 400 were investigated. The observed rate constants were shown to follow, apparent first-order kinetics in all cases. The pH rate profile shows that maximum stability of 4-DMAP was observed in the pH range 2.0 to 3.0. Acid/base catalysis of 4-DMAP was not affected by systems of various ionic strengths. Incorporation of nonaqueous propylene glycol or polyethylene glycol 400 in the pH 3.05 solution of 4-DMAP showed an increase in the stability at 55 degrees C +/- 0.5 degrees C.

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4-AminopyridineAntidotesBuffersChromatography, High Pressure LiquidDrug StabilityHydrogen-Ion ConcentrationKineticsSolventsTemperatureJournal Article

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D P Wang, L C Chang, M T Wang. 2001. Stability of 4-DMAP in solution.. https://doi.org/10.1081/ddc-100107682

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